Yun Lei^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 3021-3032, 2023, DOI:10.32604/fdmp.2023.029570

Abstract The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry. A possible way to solve this problem under deep and complex geological conditions is represented by the technology based on the phase-change induced explosion of liquid carbon dioxide. In this work, the mechanism of formation of the coal mass fracture circle resulting from the gas cracking process is theoretically analyzed. Numerical simulations show that a blasting crushing zone with a radius of 1.0 m is formed around the blasting hole.… More >

Lei Yang¹, Guangyan Huang^1,2,*, Tao Wang^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09759

Abstract In order to evaluate the blast mitigation effect of polyurethane foam in cylindrical explosion containment vessels (CECVs), a three-dimensional numerical simulation model was established. The Structured Arbitrary Lagrange-Euler (S-ALE) algorithm was applied in current simulations to define the coupling contact between TNT and Lagrange algorithm. The numerical model was verified by comparing the dynamic deformation and permanent deformation of the experiments. Based on the numerical simulation model after verification, the influence of polyurethane foam filling inside CECVs on the mitigation effect was investigated. The results revealed that compared with the ALE algorithm, the numerical simulations based on the S-ALE algorithm… More >

Xiang Li¹, Guangyan Huang^1,2,*, Zhiwei Guo^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-3, 2023, DOI:10.32604/icces.2023.09269

Abstract SPH method is widely used to study the dynamic response of metal casing under explosive loading because of its superiority in simulating metal fracture phenomenon [1-3]. The distribution of the fragment from uncoupled charge structures with segmental shaped explosive were studied. The X-ray photographic images of fragmentation obtained from explosion experiment were compared with the numerical results based on SPH method and Lagrange method. The fragmentation shows that the numerical results based on the Lagrange method are in good agreement with the experimental results while some errors appear in results based on SPH method. The velocity of the fragments at… More >

Wenbin Wu^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.08928

Abstract The shock wave and cavitation reloading caused by underwater explosion (UNDEX) could threaten the survivability of naval ships seriously. In this talk, we introduce the local discontinuous Galerkin (LDG) method [1] to solve the wave equation to track the propagation and reflection of the UNDEX shock wave. And the pressure cutoff model is adopted to simulate the cavitation effect caused by the reflection of the shock wave. The present LDG model can accurately calculate the UNDEX shock wave and cavitation loading. The present model is validated by comparing with the total formulation calculated by the ABAQUS software. Using this model,… More >

Jiahao Liu¹, Moubin Liu^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.3, pp. 1-1, 2023, DOI:10.32604/icces.2023.010056

Abstract The dynamic failure process of structures under impact and explosive loading is very common in both military and industrial fields. However, the conventional mesh-based method has some shortcomings, such as large mesh distortion and sliding surface treatment. Some typical phenomena are difficult to be simulated. The smoothed particle hydrodynamics (SPH) method has natural advantages in treating large material deformations in impact and explosion problems [1]. To make the SPH method suitable for the impact and explosion problems, it is also improved by some treatments [2] to avoid inherent stress instability and unphysical oscillation. However, numerical calculations for 3D engineering applications,… More >

Manfred Groll

Frontiers in Heat and Mass Transfer, Vol.15, pp. 1-7, 2020, DOI:10.5098/hmt.15.2

Abstract Each individual human being, groups of individuals, whole nations depend on the availability of energy for their survival. Without energy, no civilization can develop and sustain. In our globalised civilization, hundreds of millions of people cannot satisfy their needs for energy, be it in the elementary form of food, (clean) water for drinking, cooking and irrigation, (clean) air and (clean) soil for production of crops, or be it in energy required for heating/refrigeration, light, radio, TV, etc. Modern industrialized societies with their huge energy demand for industry, the transportation sector and for building up or maintaining elevated living standards for… More >

Qiushi Li^1,2,#, Ronggang Luo^1,2,#, Yu Chen³, Jinhui Xiong³, Bei Qiao¹, Xijuan Chai^1,2, Linkun Xie^1,2, Juan Wang³, Lianpeng Zhang^1,2,*, Siqun Wang⁴, Guanben Du^1,2, Kaimeng Xu^1,2,*

Journal of Renewable Materials, Vol.11, No.6, pp. 2809-2822, 2023, DOI:10.32604/jrm.2023.026184

Abstract To overcome the shortage of wood resources as well as to develop novel natural fibers materials, the Chimonobambusa quadrangularis (CQ) and Qiongzhuea tumidinoda (QT) planted in Southwest China were effectively isolated by the steam explosion (SE). The fine and uniform bamboo microfibers derived from CQ and QT were obtained, and their smallest average widths were 12.62 μm and 16.05 μm, respectively. The effects of steam explosion on the micro-morphology, chemical composition, thermal stability, crystallinity, surface wettability, and mechanical properties of bamboo microfibers were comprehensively investigated. The results showed that the relative content of cellulose in bamboo microfibers increased but the… More > Graphic Abstract

Saad Nader^1,2, Felipe Guzman³, Raphael Becar¹, César Segovia⁴, Cecilia Fuentealba³, Miguel Peirera³, Evelyne Mauret², Nicolas Brosse^1,*

Journal of Renewable Materials, Vol.10, No.2, pp. 263-271, 2022, DOI:10.32604/jrm.2022.017923

Abstract The reinforcing impact of Lignocellulosic micro and nanofibrillated cellulose (L-MNFCs) obtained from Eucalyptus Globulus bark in Urea-Formaldehyde UF adhesive was tested. L-MNFCs were prepared by an environmentally friendly, low-cost process using a combination process involving steam explosion followed by refining and ultra-fine grinding. Obtained L-MNFCs showed a web-like morphology with some aggregates and lignin nanodroplets. They present a mixture of residual fibers and fine elements with a width varying between 5 nm to 20 μm, respectively. The effects of the addition of low amounts of L-MNFCs (1% wt.) on the properties of three different adhesives (Urea-Formaldehyde UF, Phenol-Formaldehyde PF, and Tannin-Hexamine TH)… More > Graphic Abstract

Yezhi Qin, Ying Wang, Zhikai Wang^*, Xiongliang Yao

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 1093-1123, 2021, DOI:10.32604/cmes.2021.012969

Abstract The shock wave of the underwater explosion can cause severe damage to the ship structure. The propagation characteristics of shock waves near the structure surface are complex, involving lots of complex phenomena such as reflection, transmission, diffraction, and cavitation. However, different structure surface boundaries have a significant effect on the propagation characteristics of pressure. This paper focuses on investigating the behavior of shock wave propagation and cavitation from underwater explosions near various structure surfaces. A coupled Runge–Kutta discontinuous Galerkin (RKDG) and finite element method (FEM) is utilized to solve the problem of the complex waves of fluids and structure dynamic… More >

Biqing Shu^1,2, Qin Ren¹, Lu Hong¹, Zhongping Xiao², Xiaoning Lu^1,*, Wenya Wang², Junbao Yu²,Naiqiang Fu², Yiming Gu², Jinjun Zheng²

Journal of Renewable Materials, Vol.9, No.3, pp. 585-597, 2021, DOI:10.32604/jrm.2021.012932

Abstract One of the large-scale industrial applications of Moso bamboo and poplar in China is the production of standardized fiberboard. When making fiberboard, a steam blasting pretreatment without the addition of traditional adhesives has become increasingly popular because of its environmental friendliness and wide applicability. In this study, the steam explosion pretreatment of Moso bamboo and poplar was conducted. The steam explosion pressure and holding time were varied to determine the influence of these factors on fiber quality by investigating the morphology of the fiber, the mass ratio of the unexploded specimen at the end face, the chemical composition, and the… More >